Limited to the bouts I have seen, yes. The documentary Ring of Fire is a must have DVD for those who follow the sport.
Mercer/Morrison, Cooney/Norton are nasty as those are big guys getting free shots. Mercer/Jeff Pegues is rather frightening as Ray has a running start (sorry, no link that I could find). But Paret/Griffith, of course, has its own level.
Griffith-Paret 3 is worse than some others because of what happened to Paret. If you just watched the stoppage and didn't know what happened afterwards to the fighter, you'd say Williams-Jack was worse. That was like Scorsese's version of Robinson-LaMotta 6.